Muffler.



J. M. SMITH.

MUFFLER.

- APPLICATION FILED MAY 17, 1912.

1 59,644. Pa ented Apr. 22, 1913.

WITNESSES: Q I INVENTOR; if 4'. -v James M. 5 m,

ATTORNEYS UNITED STATES PATENT JAMES M. SMITH, 0F PHILADELPHIA PENNSYLVANIA, ASSIGNOR OF ONE-HALF TO CHARLES ADSIT MAGRUDER, 0F BRYN "MAWB, PENNSYLVANIA.

MUFFLER.

Specification of Letters Patent.

Patented Apr. 22, 1913.

Application filed May 17, 1912. SeriaLNo. 697,878.

To all whom it may concern:

- Be it known that I, JAMES M. SMITH, a

and State of Pennsylvania, have invented certain new and useful Improvements in Mufliers; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it apper- I employment in connection with explosive gas or other engines, for the purpose of reventing loud detonations of the exiiausted gas which is expelled after each explosion within the cylinder or cylinders of the engine, the device being peculiarly adapted to receive the exhausted gas from the engine and to permit a first expansion of the same prior to its final expulsion into the air.

The resent invention has for its pr1nc1-- pal ob ect to provide a novel and simply constructed and eflicient exhaust-mufliing device for internal combustion engines, which permits the expansion of the exploded gases passing out of the engine cylinder or cylinders, and so controls and retards the same against sudden expulsion into the air, to prevent noise or loud detonations; and, to this end the said niufiling device comprises a receiving chamber and an expansion chamber, with a gas-pressure controlled means which permits the gas to pass from the former into the latter, and means for retarding the escape of the gas from said expansion chamber into the open air.

Other objects of this invention, .not at this time more particularly enumerated, will be clearly .understood from the following detailed description of the present invention.

With the various objects of the present invention in view, the same consists, primarily, in the novel muflling device hereinafter set forth; and, the invention consists,

' furthermore, in the Various arrangements and comblnatlons of the several devices and parts, as well. as in the details of the construction of the said parts, all of which will be more fully described in the following specification, and then finally embodied in the clauses of the claims which are appended to and which form an essential part of this specification.

The invention is clearly illustrated in the i accompanying drawing, which illustrates a muffling device showing one embodiment of the principles of the present invention, the same being represented in longitudinal vertical section.

- Referring now to said drawing, the referonce-character 1 indicates a cylindrical shell providing an expansion chamber 2. Said shell 1 is closed at its upper end with a top end-plate 3, and at its bottom end with a bottom end-plate 4, said end-plates having peripheral flangesor skirts 3 and 4' which are fitted over the respective ends of said shell 1. Arranged upon the inner side of said top end-plate 3 is a flange or skirt 5, concentrically disposed with relation to said flange or skirt 3, and spaced away at a suitable distance therefrom. Said flange or skirt 5 is adapted to receive a second cylindrical shell 6, of smaller diameter, the same providing a receiving-chamber 7. Said shell 6 is closed at its bottom end by means of an end-plate 8 providedv with a peripheral flange or skirt 8 adapted to properly engage said shell 6. Said top end-plate 3 is provided with a centrally disposed tubular hub 9 which is internally screw-threaded, as at 10, to provide the gas-inlet to said receiving-chamber 7. The said screw-threads within the opening 10 provide a means for receiving the screw-threaded end of an exhaust-pipe 11,,leading from the engine cylinder or cylinders, and by means of-which the exhausted gases are conveyed to the said receiving-chamber 7 of said mufiiing device. The said top and bot-tom end-plates 3 and 4, together with said end-plate 8, are all retained in their respective closing relation with the ends of said cylindrical shells 1 and 6 by means of suitable tie-rods or struts 12,

which extend through suitable perforations and 7, formed by the said shells 1 and 6.

' The outwardly projecting free ends of said tie-rods or struts'are screw-threaded for the reception thereon of the looking or binding nuts and washers 13, whereby said tie-rods or struts are caused to hold the parts together, as will be evident; and, furthermore, each tie-rod or strut is provided with a col: lar 13', suitably secured upon the tie-rod and forming a shoulder adapted to bear against the end-plate 8, whereby the same is retained in its proper closing relation vwithin said cylindrical shell 6.

trally disposed hub 16, in which is formed an opening 17 providinga gas-outlet from said receiving chamber 7. Said pressureplate 14 is also provided, upon its respective upper and lower sides, with centrally disposed hubs 18 and 19, and extending between the hub 16 of said end-plate 8 and the hub 18 of said pressure-plate 14, with its ends seated around saidrespective hubs, is

arelief-spring 20. Said relief-spring 20 is preferably formed of a closed spiral springmember having its coils lying normally in close contact with one another. Said reliefspring is securely anchored at its respective ends, to said respective hubs l6 and 18, by means of transverselyextending retainingpins 21 and 22, which pass through the re- .spective hubs 16 and 18, so thattheir free end-portions pass through the coils of the said relief-spring 20, lying about said hubs. In this manner, saidrelief-spring is so related to said receiving-chamber 7 and said pressure-plate 14, that any downward movement of the latter tends to pull upon said relief-spring, to thereby separate its coils and to; provide intervening spaces for the escape of gas into said expansion-chamber from said receiving-chamber, .as will be clearly evident. Said bottom end-plate 4 is also provided with a centrally disposed hub 23 provided with an internally screwthreaded opening 24, adapted to provide a gas outlet from said expansion chamber 2. Said screw-threaded opening 24 permits the connection with said expansion chamber of 1 a suitable escape pipe 25, if it is so desired.

Seated upon the inner boss of said hub 23 15 one end of a retarding spring 26, the opposite end of sald spring riding freely upon the hub 19 of said pressure-plate 14, and in such a manner, so as to be guided and main tained in proper position, without, however, interfering with the proper movement of the said pressure-plate 14, or being itself affected by themovement of said pressure.- plate, thus retaining said retarding-spring in proper alinement with the outlet-opening 24 ,of the expansion-chamber 2. Said retarding-spring 26 is preferably normally compressed, so that itscoils will lie in close contact with each other. I

In operation, the exhaust gases are expelled from the cylinder or cylinders of the engine, and are conveyed through the exhaust pipe 11, from which they enter the receiving-chamber -7, wherein a certainamount of expansion of the gases takes place. The gas is, quickly forced out of said receiving chamber through the outlet opening 17, and following the path of least resistance, passes through the interior of the said relief-spring 20, thus being carried into contact with sald pressure-plate 14. The expansive force of the gases, together with the force of its expulsion from the enginecylinder or cylinders, operates upon said pressure-plate 14, so as to force the same in a downward direction, the movement of the pressure-plate thus produced, pulling upon said relief -spring 20 thereby tending to separate the coils thereof, and thus providing intervening spaces or interstices throughout the length of the spring, through which the gases may both expand and flow into said expansion-chamber, the gases in the meantime having expended a large part of their force in opening this escape. VVithin said'expansion-chamber, the said gases undergo a further expansion and a consequentdiminution "of pressure, and then finally forcethemselves through the coils of said retarding-spring 26, at a further expenditure of their force and energy, and thence pass or flow quickly, but quietly, through said outlet-opening 24 int-o said escape-pipe 25, and finally into the open air.

It will thus be readily understood, that by the time the gases are thus passed into the open air, thegreatest art of their expansive force has been relieved within the novel mufliing device, and their sudden expulsion into the open air'is pro erly checked and retarded; consequently, tie gases are finally expelled noiselessly and without the usual sharp detonations generally accompanying their sudden and direct escape from the confined space of the ordinary exhaustpipe.

The above-described mufiiin'g device provides, therefore, a very simple and eflicient construction of device for controllin the venting of exhaust-gases, the same being self-acting, of few parts, easily and cheaply manufactured and assembled, and little likely to be disarranged or disordered during the operation and use of the device. Furthermore, the mulfiing-device is cons ructed so as not to be injuriously affected therethrough for coo-ling the-same by the pressure of any water within the same, and if desired, wat'er may'be passed operation.

I am aware that changes may be made in the various arrrangements and combinations of the several, devices andparts, as well as in the details of the construction of the same, without departing from 'the scope ofthe present invention as herein set forth, I and as defined in the clauses of the claims which are appendedthe'reto. Hence, I do not limit my invention to the exact arrangements and combinations of the several devices and parts as described in the said specification, nor' do I confine myself to the exact details of the construction of the said parts, as illustrated in the accompanying drawings. I claim: 1. A mufiiing device comprisinga shell providing a receiving-chamber having a gas-inlet and a gas-outlet, a movable pressure-plate, a relief-spring arranged between said gas-outlet of said receiving-chamber and said pressure plate, a shell surrounding said relief-spring and said pressure-plate so as to provide an expansion-chamber, and means for securing said relief-spring in connection with said pressure-plate, whereby the downward movement of the latter opens the coils of said relief-spring so as to permit the gas to enter said expansion-chamber from said receiving-chamber.

2. A mufiling device comprising a shell providing a receiving-chamber having. a

gas-inlet and a gas-outlet, a movable pressure-plate, a relief-spring arranged between said gas-inlet of said receiving-chamber and said pressure-plate, a shell surrounding said relief-spring and said pressure-plate so as to provide an expansion-chamber, and means for securing said relief-spring in connection with said pressure-plate, whereby the downward movement of the latter opens the coils of said relief-spring so as to permit the gas to enter said expansion-chamber from said receiving-chamber, means connected with said expansion-chamber providing a gas-outlet, and means for retarding the flow of gases out of said expansionchamber.

3. A mufiiing device comprising a chambered body providing an expansion-chamber, a chambered body providing a receiving-chamber, means providing communication between said receiving-chamber and said expansion-chamber, means for normally closing said "means of communication,

when in 4, In a' mufller, the combination with a cylindrical shell forming an expansion-- passage thereof, another end-plate con-' nected with said second cylindrical shell having an opening afl'ording communication between said receiving-chamber and saidexpansion-chamber, tie-rods for securing said shells and end-plates in their assembled relation, a pressure-plate slidably supported within said expansion-chamber, and a spiral relief-springhaving its coils normally compressed so as to lie in close contact with one another, said relief-spring being secured at one end to said end-plate of said receiving chamber and in alinement with the said gasoutlet of said receiving-chamber and at the other end to said pressure-plate.

5. In a mufiier, the combination with a cylindrical shell forming an expansionchamber, of end-plates provided with openings forming inlet and outlet gas passages, a second cylindrical shell forming a receiving chamber connected with one of said end plates, and registering with the inlet gas passage thereof, another end-plate connected with said second cylindrical shell having an opening affording communication between said receiving-chamber and said expansion-chamber, tie-rods for securing said shells and end-plates in their assembled re.-

lation, a pressure-plate slidably supported within said expansion-chamber, and aspiral relief-spring having its coils normally compressed so as to lie in close contact w1th one another, said relief-spring being secured at one end to said end-plate of said receivingchamber and in alinement with the said gasoutlet of said receiving chamber and at the other end to said pressure-plate',and means connected with the outlet gas-passage of said expansion-chamber for retarding the outward flow of gases therefrom.

6. In a muflier, the combination with a cylindrical shell forming an expansionehamber, of end-plates provided with openings forming inlet and outlet gas passages, a second cyhndrical shell forming a receiving chamber connected with one of said endplates and registering with the inlet gas passage thereof, another end-plate connected with said second cylindrical shell having an opening affording communication between said receiving-chamber and said expansion-chamber, tie-rods for securing said shells and end-plates in their assembled re lation, a pressure-plate slidably supported within said expansion-chamber, and a spiral one end to said end-plate of said receivingsupporting said retarding-spring in such 10 chamber and in alinement with the said gasconnection.

outlet of said receiving chamber and at the Intestimony, that I claim the invention other end to said pressure-plate, a retarding set forth above I have hereunto set my hand spring having its coils normally compressed this sixth day of April, 1912.

so as to lie in close contact with one another JAMES M. SMITH. and arranged Within said eXpansion-cham- Witnesses: her in alinement With the outlet gas-passage JOSEPH M. BAKER,

'of said expansion-chamber, and means for CHAS. A. MAGRUDER. 

